Question

我正在尝试使用dom4j 1.6.1使用XPath遍历以下文档。我正在寻找<query>元素的数量。

<?xml version="1.0" encoding="UTF-8"?>
<reportLineageResponse>
   <querySet expressionLocale="en-us">
      <queries xmlns="http://developer.cognos.com/schemas/report/9.0/">
         <query name="Top 10 Sales Staff List"/>
         <query name="Top 10 Sales Staff by Quantity List"/>
         <query name="Sales Figures America Region Combination Chart"/>
      </queries>
   </querySet>
</reportLineageResponse>

这是调用dom4j的代码。

int numberOfQueries(org.w3c.dom.Document jaxpDocument) {
    DOMReader domReader = new DOMReader();
    org.dom4j.Document document = domReader.read(jaxpDocument);

    Map<String, String> nsMap = Collections.singletonMap("rep", "http://developer.cognos.com/schemas/report/9.0/");
    XPath queryXp = document.createXPath("/reportLineageResponse/querySet/rep:queries/rep:query")
    queryXp.setNamespaceURIs(nsMap);
    List<Node> queries = queryXp.selectNodes(document);
    return queries.size();
}

我正确指定了命名空间，但得到0结果。可能是什么问题？

编辑：如果我在创建它之后查看dom4j.Document，它的命名空间就错了：

<?xml version="1.0" encoding="UTF-8"?>
<reportLineageResponse>
   <querySet expressionLocale="en-us">
      <queries xmlns="http://developer.cognos.com/schemas/report/9.0/">
         <query xmlns="" name="Top 10 Sales Staff List"/>
         <query xmlns="" name="Top 10 Sales Staff by Quantity List"/>
         <query xmlns="" name="Sales Figures America Region Combination Chart"/>
      </queries>
   </querySet>
</reportLineageResponse>

编辑：这是创建org.w3c.dom.Document的代码：

Document loadDocument(URL url) {
    InputStream stream = url.openStream();
    DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
    Document result = docBuilder.parse(stream);
    stream.close();
    return result;
}

Answer 1

按如下方式更改xml加载：

DocumentBuilderFactory docBuilderFactor = DocumentBuilderFactory.newInstance();
docBuilderFactor.setNamespaceAware(true);
DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();

dom4j中的XPath评估从org.w3c.dom.Document创建的文档无法按预期工作

1 个答案: